# Time-Dependent Deflections (TS500)

Time dependent deflection calculation and control for beams are made automatically according to

**TS 500 13.2.3**.

Time dependent deflection calculation and control for slabs are made automatically according to

**TS 500 13.2.3**.

Deflection limits are determined by the user.

**Notation**

**l _{n}**

**Span length of beam or one-way slab**

_{ }=*= Total deflection*

**δ**_{t}*= Instantaneous deflection*

**δ**_{i}*= Instantaneous deflection due to permanent loads*

**δ**_{ig }*= Time-dependent favtor for sustained load*

**γ**_{t}*= Multiplier used for additional deflection due to long-term effects*

**λ***= Compression reinforcement ratio*

**ρ'**The total deflection, including the time dependent deflection can be obtained by using **TS 500 Article 13.2.3**.

The total deflection value is considered as the sum of the instantaneous deflection, * δ_{i}* and the deflection of permanent loads

*. The time dependent deflection calculation is shown in*

**λδ**_{ig}**Equation 13.3**.

Multiplier used for additional deflection due to long-term effects * λ* is calculated according to

**Equation 13.4**. In

**Equation 13.4**

*is compression reinforcement ratio and*

**ρ'***is considered as a Time-dependent favtor for sustained load.*

**γ**_{t}Permanent deflection multiplier * γ_{t}* is taken as 2.0 based on 5 years or more loading time in accordance with

**Table 13.2.**

Allowable maximum deflections for flexural members are given in **TS500 Table 13.3**.

Deflection limits can be adjusted in the **Cracking / Deflection** tab of the **Beam Settings** window .

The deflection limits conditions can be adjusted in the **Deflection** tab of the **Tiling Settings** window .

Deflection results can be examined in the **Deflection & Crackings** tab of the **Beam Reinforcements **window .

**The** results of Instantaneous deflection and time-dependent deflection of beams can be examined from the **Beam Deflection and Crack Control** report.

The results of Instantaneous deflection and time-dependent deflection of the slabs can be examined from the **Slab Deflection Control** report.